Looking for the Holy Grail

As mentioned yesterday, world coal consumption is growing fast, a trend that we need to stop and reverse. Right now the biggest competitor to coal is probably natural gas, but to truly solve our environmental problems, we need to move to carbon-free clean energy sources like wind and solar power. But sometimes the wind doesn't blow and the sun doesn't shine, that's why large-scale energy storage represents a 'holy grail' to those who try to design tomorrow's power grid.

EOS Energy Website/Screen capture

Prototypes Claimed to Have 2x Density of Lithium-Ion Batteries

EOS Energy Storage is a startup that claims to have developed a type of zinc-air battery that would be suitable to store large quantities of energy at a low cost and without performance degradation for thousands of charge cycles. If it works as claimed - and that's a big "if" - it could allow wind and solar to become a much larger portion of energy generation than they can with our current grid, and it could replace natural gas peakers (the plants that only turn on during peak demand).

The technical highlights, according to EOS, are that its zinc-air battery could last for around 30 years (they claim to have reached 2,700 cycles without degradation) at about half of what additional natural gas would cost. The company wants to sell megawatt-scale batteries with 6 hours of storage at a capital cost of $160 per kilowatt-hour. They could be used to store energy at times of low demand to then release it during peak time, acting as a kind of damping buffer. They could not only be used to absorb the daily demand cycles, but also to store renewable energy from intermittent sources; for example, it could store energy from a wind farm over a windy night and then release it to the grid the next day during peak demand time. This is something that grid-connected electric cars can also help with, especially if we have a smart grid that can communicate with them.

EOS Energy Storage is currently raising funding from investors and will start taking pre-orders in the Spring of 2012, but it's not clear when they'll start shipping batteries. If their claims are accurate, I hope that they'll be able to ramp up production quickly and get to large scale deployment soon, because we really need more energy storage on the grid.